Access door control apparatus for controlled emission incinerator

ABSTRACT

The improvement, in a controlled emission incinerator apparatus having a main combustion chamber including an access door mounted for movement between an open position for loading of material and a closed position for burning of the material loaded and an independent secondary combustion chamber for burning the products of incomplete combustion from the main combustion chamber, of apparatus for preventing undesirable emissions from the incinerator resulting if material for burning is loaded into the incinerator when the temperatures in both the combustion chambers are not in the desired range. The apparatus comprises devices independently responsive to temperatures within both combustion chambers for selectively allowing movement of the access door from the closed position to the open position only when desired temperature ranges are present in both the main and secondary combustion chambers.

United States Patent Clements [451 June 13, 1972 [72] lnventor: Richard F. Clements, Charlotte, NC.

[73] Assignee: Environmental Control Products Inc.,

I Charlotte, NC.

[22] Filed: Jan. 25, 1971 [21] Appl.No.: 109,387

[52] US. Cl. ..110/8 A, 110/18 C, 110/173,

3,489,109 l/197O Flowers, Jr. ..110/18 3,602,161 8/1971 Wyrough ..110/18 Primary Examiner-Kenneth W. Sprague Attorney-Parrott, Bell, Seltzer, Park & Gibson 57] ABSTRACT The improvement, in a controlled emission incinerator apparatus having a main combustion chamber including an access door mounted for movement between an open position for loading of material and a closed position for burning of the material loaded and an independent secondary combustion chamber for burning the products of incomplete combustion from the main combustion chamber, of apparatus for preventing undesirable emissions from the incinerator resulting if material for burning is loaded into the incinerator when the temperatures in both the combustion chambers are not in the desired range. The apparatus comprises devices independently responsive to temperatures within both combustion chambers for selectively allowing movement of the access door from the closed position to the open position only when desired temperature ranges are present in both the main and secondary combustion chambers.

7 Claims, 3 Drawing Figures PATENTEnJuu 1 a ma 3. 669 040 sum 20F 2 INVENTORI RxcHAeo F. CLEMENTS ATTORNEYS ACCESS DOOR CONTROL APPARATUS FOR CONTROLLED EMISSION INCINERATOR This invention relates to access door control apparatus for a controlled emission incinerator for preventing undesirable emissions from the incinerator resulting if material for burning is loaded into the incinerator when the temperatures in both the combustion chambers are not in the desired ranges.

This invention is an improvement to a controlled emission incinerator. apparatus of the type disclosed in U.S. Pat. No.

3,543,700, issued Dec. 1, 1970, and assigned to the present assignee. This controlled emission incinerator apparatus includes a main combustion chamber for burning of waste material including an access door for movement between an open position for loading of material to be burned and a closed position for burning of the material loaded and an independent secondary-combustion chamber for burning of the products of incomplete combustion received from the main combustion chamber.

In the use of this type of controlled emission incinerator apparatus, excessive or undesirable emissions from the incinerator can result if the incinerator is operated at temperatures other than within its programmedtemperature ranges, such as when the temperature in the secondary combustion chamber has .not reached a range of ignition for the products of incomplete combustion or the temperature in the primary combustion chamber has exceeded a predetermined temperature range which directly indicates that combustion is occurring at a rate which will produce excessive amounts of product gases. Also, undesirable emissions occur if too much material is loaded into the incinerator for'burning or if the'burning cycle of the material in the incinerator is cut short.

Accordingly, it is the object of this invention to provide improved means for a controlled emission incinerator apparatus, of the type described above, which will prevent undesirable emissions from the incinerator.

It has been found by this invention that the above object may be accomplished by providing means, in a controlled emission incinerator of the type discussed above, comprising means for selectively allowing and preventing movement of the access door from the closed position to the open position for respectively allowing loading of material to be burned and preventing loading of material to be burned, and means independently responsive to temperatures within both'the main combustion chamber and the secondary combustion chamber for controlling the means for selectively allowing and preventing movement of the access door so as to allow movement of the access door from the closed position to the open position only when the desired temperature ranges are present in both the main and secondary combustion chambers.

Preferably, the means for selectively allowing and preventing movement of the access door comprises motor means for moving the access door from a closed position to an open position and from the open position to the closed position. Preferably, the control means comprises an electrical circuit operatively associated with the motor means and including separate temperature sensors positioned in the main combustion chamber and the secondary combustion chamber for activating the electrical circuit control means to allow the motor means to move the access door'to the open position only when the temperature in the main combustion chamber has not exceeded a predetermined range and when the temperature in the secondary combustion chamber has reached a predetermined range. Also, the preferred embodiment of this.

invention includes timer means for controlling the motor means so that the access door will remain in the open position for loading of material to be burned only a predetermined time period to limit the amount of material loaded and so that the access door will remain in theclosed position at least a predetermined period of time for complete burning of the loaded material.

Some of the objects of the invention having been stated, other objects will-appear as the description proceeds when taken in conjunction with the accompanying drawings, in

which:

FIG. 1 is a perspective view of a controlled emission incinerator apparatus incorporating the improvements of this invention;

FIG. 2 is a cross-sectional, elevational view of the controlled emission incinerator apparatus of F IG. 1; and

FIG. 3 is a schematic view illustrating the improvements of this invention.

Referring now to the drawings, FIGS. 1 and 2 illustrate a controlled emission incinerator apparatus which, as discussed above, is of the type disclosed in US. Pat. No. 3,543,700, issued Dec. 1, 1970, and assigned to the assignee of the present invention. This incinerator apparatus is broadly indicated in the drawings by the reference numeral 10 and includes a first, generally horizontally-extending, enclosed, hollow housing 12 defining internally a main combustion chamber 13 for the burning of waste material therein.

The housing 12 defining the main combustion chamber 13 includes an access opening 16 in the front wall thereof which is covered by a door 17 suitably shaped to completely close the opening 16 when in the closed position illustrated in FIGS. 1 and 2. The door 17 is suitably mounted in trackways 20 and 21 for moving from the closed position, illustrated in FIGS. 1 and 2, to an open position completely exposing the opening 16 in the housing 12 for the loading of material into the main combustion chamber 13.

For moving the door 17 between the closed position and, the open position, up and down along the trackways 2 0 and 21, the door 17 is mounted on the ends of chain members 22 and 23 which extend around sprockets 24 and 25, respectively. Sprockets, 24 and 25 are mounted on a rotatable shaft26 which is suitably mounted for rotation in bearing members secured to the trackways 20 and 21 vor to suitable support frame members. The shaft 26 also includes pulleys 27 and 28 secured thereto and around which pass suitable belts 30 and 31. The belts 30 and 31 also pass around respective pulleys 32 and 33 leading from a suitable gearing unit 35 which is operatively connected to and driven by a reversible electric motor 36. The otherends of the chain members 22 and 23 may include suitable weights 37 attached to the ends thereof or may be anchored in any suitable manner such that when the motor 36 rotates the shaft 26, the door 17 will be moved from either the closed to the open position or from the open to the closed position, depending upon the direction of rotation of the motor 36.

The controlled emission incinerator apparatus 10 further comprises a second, independent, generally horizontally-extending, enclosed, hollow housing 40 defining internally a secondary combustion chamber 41 for receiving the products of incomplete combustion from the main combustion chamber 13 for burning the same therein. Also'included is a generally vertically-extending, hollow, transition conduit 45 having the bottom end thereof opening into the main combustion chamber 13 and the upper end thereof opening into the secondary combustion chamber 41 for providing a flow and path of travel for the products of incomplete combustion from the main combustion chamber 13 to the secondary combustion chamber 41. The controlled emission incinerator apparatus further includes a generally vertically-extending, open-ended, exhaust stack means having one end thereof communicating with the interior of the secondary combustion chamber 41 and the other end thereof opening into the atmosphere for allowing the exhaustion of gases remaining after burning in the secondary combustion chamber 41.

Proper control of the operation of the electric motor 36 and the door 17 are important in the overall operation of the controlled emission incinerator apparatus 10. Excessive emissions can result if the incinerator 1.0 is operated at temperatures other than within its programmed temperature ranges. The undesirable conditions can occur when the temperature in the secondary combustion chamber has not reached the ignition range of the combustion product gases or the products of incomplete combustion, or when the temperature in the primary combustion chamber has exceeded a predetermined range which directly indicates that combustion is occurring at a rate which will produce excessive amounts of product gases.

To exercise control over the loading and burning of material in the incinerator 10, an electrical control circuit, as schematically illustrated in FIG. 3, is provided which will permit the door 17 to be opened only when the incinerator temperatures are within the described correct operating ranges. Also, additional circuitry is incorporated for automatically limiting the time the door 17 will remain open for loading, and once closed, prevent the opening of the door 17 for an additional period of time. The first timed period limits the amount of material capable of being loaded per cycle and the second timed period spaces the loads throughout the burning schedule.

Referring now specifically to FIG. 3 of the drawings, a conventional fuel type burner 60 is ignited and the incinerator 10, including the primary and secondary combustion chambers 13 and 41, proceeds through its warm-up phase. When the lower limit of the temperature range for efficient incineration has been reached, e.g.,- 600 F., in the secondary combustion chamber 41, a thermocouple type temperature sensor 61 and its controlling indicator 62 closes solenoid switch 63. Current can now flow through solenoid switch 64, which is normally closed, through solenoid switch 63, through the door open limit switch 65, and to the timer circuit 67. The timer circuit 66 is a door open timer and the timer circuit 67 is a door closed timer and these timers are controlled by normally closed contacts on an open motor control relay 70 and a close motor control relay 71, respectively. Either motor control relay 70 or 71, when energized, opens a set of control contacts which resets its respective timer. When either motor control relay de-energizes, its set of contacts closes and thus starts the respective timer. Assuming both motor control relays 70 and 71 have been de-energized a sufficient time to permit the timers 66 and 67 to complete their timing interval, contacts 67a and 66a will have closed and contacts 6612 will have opened.

The current available through the temperature sensing circuit previously described can now flow through the closed set of timer contacts 67a, and through the closed set of switch contacts on the door close position limit switch 73. (This switch is shown'actuated and held by the door being in its closed position.) Depressing the open operator push button 75 closes its set of normally open contacts and completes the circuit to the open motor control relay solenoid 70 which closes the power contacts 70a and thereby provides current to the electric motor 36 to turn the same in a direction to move the door 17 to its open position. As long as the open operator push button 75 is depressed, the door 17 will continue to move toward the open position until it reaches its fully open position and actuates the door open position limit switch 65 which breaks the circuit, de-energizing the open motor control relay 70. The door may be stopped in any position be releasing the open operator push button 75 which also breaks the circuit.

When the open motor control relay 70 de-energizes, its set of control contacts starts the door open timer 66. When the door open timer 66 times out, its contacts 66b will open and contacts 66a will close. The contacts 66b prevent the door opening circuit from being energized, while the contacts 66a complete the door closing circuit through the normally closed set of switch contacts on the door close position limit switch 73, through the normally closed contacts of the open operator push button 75, and energizes the close motor control relay 71 which closes the power contacts 710. This will deliver current to the electric motor 36 and cause it to rotate in a direction to close the door 17. The door will continue in its closing path of travel until it actuates the close position limit switch 73 and breaks the closing circuit. The door 17 may be temporarily stopped by depressing the open operator push button 75 which also breaks the closing circuit, but is prevented from opening by the energized open contacts 66b. However, when the push button is released the door will continue to close.

Once the door has closed, it cannot be opened until the door close timer 67, started when the close motor control relay 71 de-energized closing its timer control contacts, has timed out.

If the temperature in the main combustion chamber exceeds the upper limit of the desired temperature range, e.g. 2,000 F., a thermocouple type sensor 82 and its indicator 83 will open solenoid switch 64 preventing the door from being opened until the temperature has reduced to within the operating range.

Although a preferred control circuit has been illustrated in FIG. 3 and described above, it is to be understood that other types of control circuits could be designed which perform the improved functions set forth above. By this invention it may be seen that there has been provided an access door control apparatus for a controlled emission incinerator which prevents undesirable emissions from the incinerator by controlling the operation of the door responsive to temperatures in both the primary and secondary combustion chambers.

In the drawings and specification there has been set forth a preferred embodiment of the invention and, although specific terms are employed, they are used in a generic and descriptive sense only and not for purposes of limitation.

What is claimed is:

1. In a controlled emission incinerator apparatus having a main combustion chamber for burning of waste material including an access door mounted for movement between an open position for loading of material to be burned and a closed position for burning of the material loaded and an independent secondary combustion chamber for burning the products of incomplete combustion received from the main combustion chamber; the improvement of means for preventing undesirable emissions from the incinerator resulting if material for burning is loaded into the incinerator when the temperatures in both the combustion chambers are not in the desired ranges, said means comprising:

means for selectively allowing and preventing movement of the access door from the closed position to the open position for respectively allowing loading of material to be burned and preventing loading of material to be burned; and

means independently responsive to temperatures within both the main combustion chamber and the secondary combustion chamber for controlling said means for selectively allowing and preventing movement of the access door so as to allow movement of the access door from the closed position to the open position only when desired temperature ranges are present in both the main and secondary combustion chambers.

2. In a controlled emission incinerator apparatus, as set forth in claim 1, in which said control means includes timer means for controlling said means for selectively allowing and preventing movement of the access door so that the access door will remain in the open position for loading of material to be burned only a predetermined time period to limit the amount of material loaded and so that the access door will remain in the closed position at least a predetermined period of time for complete burning of the loaded material.

3, In a controlled emission incinerator apparatus, as set forth in claim 1, in which said control means includes separate temperature sensors positioned in the main combustion chamber and the secondary combustion chamber for activating said control means to allow the access door to move to the open position only when the temperature in the main combustion chamber has not exceeded a predetermined range and when the temperature in the secondary combustion chamber has reached a predetermined range.

4. In a controlled emission incinerator apparatus having a main combustion chamber for burning of waste material including an access door mounted for movement between an open position for loading of material to be burned and a closed position for burning of the material loaded and an independent secondary combustion chamber for burning the products of incomplete combustion received from the main combustion chamber; the improvement of means for preventing undesirable emissions from the incinerator resulting if material for burning is loaded into the incinerator when the temperatures in both the combustion chambers are not in the desired ranges, said means comprising:

motor means for selectively moving the access door from a closed position to an open position for allowing loading of material to be burned and for moving the access door from the open position to the closed position to prevent loading of material to be burned; and

electrical circuit control means independently responsive to temperatures within both the main combustion chamber and the secondary combustion chamber for controlling said motor means for selectively allowing and preventing movement of the access door so as to allow movement of the access door from the closed position to the open position only when desired temperature ranges are present in both the main and secondary combustion chambers.

5. In a controlled emission incinerator apparatus, as set forth in claim 4, in which said electrical circuit control means includes timer means therein for controlling said motor means so that the access door will remain in the open position for loading of material to be burned only a predetermined time period to limit the amount of material loaded and so that the access door will remain in the closed position at least a predetermined period of time for complete burning of the loaded material. a v

6. In a controlled emission incinerator apparatus, as set forth in claim 4, in which said electric circuit control means includes separate temperature sensors positioned in the main combustion chamber and the secondary combustion chamber for activating said electrical circuit control means to allow said motor means to move the access door to the open position only when the temperature in the main combustion chamber has not exceeded a predetermined range and when the temperature in the secondary combustion chamber has reached a predetermined range.

7. In a controlled emission incinerator apparatus having a main combustion chamber for burning of waste material including an access door mounted for movement between an open position for loading of material to be burned and a closed position for burning of the material loaded and an independent secondary combustion chamber for burning the products of incomplete combustion received from the main combustion chamber; the improvement of means for preventing undesirable emissions from the incinerator resulting if material for burning is loaded into the incinerator when the temperatures in both the combustion chambers are not in the desired ranges, said means comprising:

motor means for selectively moving the access door from a closed position to an open position for allowing loading of material to be burned and for moving the access door from the open position to the closed position to prevent loading of material to be burned; and

electrical circuit control means for controlling said motor means for selectively allowing and preventing movement of the access door, said electrical circuit control means including separate temperature sensors positioned in the main combustion chamber and the secondary combustion chamber for activating said electrical circuit control means to allow said motor means to move the access door to the open position only when the temperature in the main combustion chamber has not exceeded a predetermined range and when the temperature in the secondary combustion chamber has reached a predetermined range and timer means for controlling said motor means so that the access door will remain in the open position for loading of material to be burned only a predetermined time period to limit the amount of material loaded and so that the access door will remain in the closed position at least a'predetermined period of time for complete burning of the loaded material. il 

1. In a controlled emission incinerator apparatus having a main combustion chamber for burning of waste material including an access door mounted for movement between an open position for loading of material to be burned and a closed position for burning of the material loaded and an independent secondary combustion chamber for burning the products of incomplete combustion received from the main combustion chamber; the improvement of means for preventing undesirable emissions from the incinerator resulting if material for burning is loaded into the incinerator when the temperatureS in both the combustion chambers are not in the desired ranges, said means comprising: means for selectively allowing and preventing movement of the access door from the closed position to the open position for respectively allowing loading of material to be burned and preventing loading of material to be burned; and means independently responsive to temperatures within both the main combustion chamber and the secondary combustion chamber for controlling said means for selectively allowing and preventing movement of the access door so as to allow movement of the access door from the closed position to the open position only when desired temperature ranges are present in both the main and secondary combustion chambers.
 2. In a controlled emission incinerator apparatus, as set forth in claim 1, in which said control means includes timer means for controlling said means for selectively allowing and preventing movement of the access door so that the access door will remain in the open position for loading of material to be burned only a predetermined time period to limit the amount of material loaded and so that the access door will remain in the closed position at least a predetermined period of time for complete burning of the loaded material.
 3. In a controlled emission incinerator apparatus, as set forth in claim 1, in which said control means includes separate temperature sensors positioned in the main combustion chamber and the secondary combustion chamber for activating said control means to allow the access door to move to the open position only when the temperature in the main combustion chamber has not exceeded a predetermined range and when the temperature in the secondary combustion chamber has reached a predetermined range.
 4. In a controlled emission incinerator apparatus having a main combustion chamber for burning of waste material including an access door mounted for movement between an open position for loading of material to be burned and a closed position for burning of the material loaded and an independent secondary combustion chamber for burning the products of incomplete combustion received from the main combustion chamber; the improvement of means for preventing undesirable emissions from the incinerator resulting if material for burning is loaded into the incinerator when the temperatures in both the combustion chambers are not in the desired ranges, said means comprising: motor means for selectively moving the access door from a closed position to an open position for allowing loading of material to be burned and for moving the access door from the open position to the closed position to prevent loading of material to be burned; and electrical circuit control means independently responsive to temperatures within both the main combustion chamber and the secondary combustion chamber for controlling said motor means for selectively allowing and preventing movement of the access door so as to allow movement of the access door from the closed position to the open position only when desired temperature ranges are present in both the main and secondary combustion chambers.
 5. In a controlled emission incinerator apparatus, as set forth in claim 4, in which said electrical circuit control means includes timer means therein for controlling said motor means so that the access door will remain in the open position for loading of material to be burned only a predetermined time period to limit the amount of material loaded and so that the access door will remain in the closed position at least a predetermined period of time for complete burning of the loaded material.
 6. In a controlled emission incinerator apparatus, as set forth in claim 4, in which said electric circuit control means includes separate temperature sensors positioned in the main combustion chamber and the secondary combustion chamber for activating said electrical circuit control means to allow said motor means to move the access door to the open position only wHen the temperature in the main combustion chamber has not exceeded a predetermined range and when the temperature in the secondary combustion chamber has reached a predetermined range.
 7. In a controlled emission incinerator apparatus having a main combustion chamber for burning of waste material including an access door mounted for movement between an open position for loading of material to be burned and a closed position for burning of the material loaded and an independent secondary combustion chamber for burning the products of incomplete combustion received from the main combustion chamber; the improvement of means for preventing undesirable emissions from the incinerator resulting if material for burning is loaded into the incinerator when the temperatures in both the combustion chambers are not in the desired ranges, said means comprising: motor means for selectively moving the access door from a closed position to an open position for allowing loading of material to be burned and for moving the access door from the open position to the closed position to prevent loading of material to be burned; and electrical circuit control means for controlling said motor means for selectively allowing and preventing movement of the access door, said electrical circuit control means including separate temperature sensors positioned in the main combustion chamber and the secondary combustion chamber for activating said electrical circuit control means to allow said motor means to move the access door to the open position only when the temperature in the main combustion chamber has not exceeded a predetermined range and when the temperature in the secondary combustion chamber has reached a predetermined range and timer means for controlling said motor means so that the access door will remain in the open position for loading of material to be burned only a predetermined time period to limit the amount of material loaded and so that the access door will remain in the closed position at least a predetermined period of time for complete burning of the loaded material. 